ELSiVIER Solar Energy Materials and Solar Cells 37 (1995) 133-142 Optimization of photoelectrochemical solar cells based on polycrystalline CdTe film photoanode Shikha Mishra, Sanjay Tiwari *, B.P. Chandra Department of Postgraduate Studies and Research in Physics, Rani Durgavati University, Jabalpur 482 001, India Received 20 October 1994 Abstract Polycrystalline films of CdTe were electroplated onto titanium substrates from acidic baths. When surface treated, these layers show good photoelectrochemical behaviour in a polysulphide electrolyte with high conversion efficiencies and stability. The solid state parameters of the films annealed are calculated and compared with those of unannealed film based cells. Donor densities are found to be in the range of 1Ol4 cmm3. Chemical etching improves the short-circuit current and fill factor and also results in Fermi level pinning of the photoanode, whereas photoelectrochemical etching improves the stability of the photoanode in polysulphide electrolyte. 1. Introduction Recently there has been much interest in the application of n-type semiconduc- tor electrodes to photoelectrochemical solar cells (PEC) for solar energy conver- sion [ll. For the construction of a PEC cell capable of efficient solar energy conversion, several important criteria must be met. First, the semiconductor material should have a band gap energy (E,) small enough to utilize the solar spectrum sufficiently [2]. Secondly, semiconductor electrodes must be stable against photoanodic reactions. Due to the above reasons Cadmium-telluride is an impor- tant material for PEC solar cells. Polycrystalline CdTe has shown great promises as a photoanode in polysulphide redox electrolyte for solar energy conversion through PEC cells [3,4]. However, because of inherent defects present in the polycrystalline materials, a considerable portion of the photogenerated charge carriers is lost due * Corresponding author. Department of Physics, Government Autonomous Science College, Jabalpur 482 001, India. 0927-024&J/95/$09.50 0 1995 Elsevier Science B.V. All rights reserved SSDI 0927-0248(94)00202-9